A cross flow fan is a blower which extends in the axial direction and includes a plurality of vanes lined up in the rotational direction. In an air conditioner including this cross flow fan, a stabilizer and a rear guider are provided to oppose the outer periphery of the fan, respectively. The stabilizer is termed a front tongue portion, whereas a part of the rear guider which part extends from the leading end portion to the portion closest to the fan is termed a rear tongue portion. These tongue portions form an air passage on the blow-out side of the fan. Between each tongue portion and the fan, a vortex airflow is generated. When a vane of the fan passes this vortex airflow, wind noise (NZ noise) is generated on account of the interference between the vortex airflow and the vane.
To suppress this wind noise, for example, Patent Document 1 teaches that a rib protruding toward the fan is provided at the leading end portion of the front tongue portion (stabilizer). The rib is arranged on the fan side such that the edge (which is closest to the fan) of the surface is corrugated to have apexes which are deviated from one another in the direction of the rotation. With this arrangement, the edge of one vane does not simultaneously passes the apexes of the rib, and hence the generation of wind noise is temporally spread. In this way, the wind noise is suppressed.